Safety-clutch for power-driving pumps.



parts.

PATENT OFFICE.

WILLIAM ITENRY HEARD, OF LONDON, ONTARIO, CANADA.

SAFETY-CLUTCH FOR POWER-DRIVING PUMPS.

Specification of Letters Patent.

Patented Jan. 7, 1908.

Application filed July 11. 1906. Serial No. 325,609. Renewed November 9. 1907- Serial No. 401.493.

T 0 all whom it ma concern:

Be it known t at I, WILLIAM ITIENRY HEARD, of the city of London, in the county of Middlesex, Province of Ontario, Canada, have invented certain new and useful Imrovements in. a Safety-Clutch for Powerriving Pumps, of which the following is a specification.

My object is to devise means whereby a power driven pump may be automatically regulated toprevent the pressure inpump rising above a predetermined maximum, and

my invention consists-essentially of a clutch whereby the driving part may be put in gear or-out of gear with the driven part and of means whereby increase of pressure in a fluid conduit will throw the, clutch out of gear untilsuch time as the pressure decreases, substantially as hereinafter more specific-ally described and then definitely claimed.

1 is a plan view of my improved Fig. 2 is a similar View of part of the same, showing the clutch disengaged. Fig. 3 is a vertical section of thepipe connections for the cylinder.

In the drawings like letters of reference indicate corresponding parts in the different figures.

A is the frame supporting the different I) is a shaft or driving member suitably journaled on theyfriame. This shaft may be driven in any; lsuitable manner. Loose on the shaft is a ear wheel E. On the hub of this gear wheel is formed one half ofa clutch. F is the movable clutch memher adapted to en age with the part of the clutch formed on t e hub of the wheel. The ear wheel when in clutch with the shaft is intended to drive a suitable pump. The movable part of the clutch has a sleeve G formed on or connected therewith, provided with a'helical groove H. I is a coil spring normally tending to maintain the clutch in ear. g B is a base plate on which is formed or se cured the cylinder C. With this cylinder communicates a conduit J. This conduit when the machine is in operation will be ,connected by means of a connection a with the pressure side of the pump with which the safety clutch is to be used and by means of the connection I) with the spray nozzles, as

this device will mostly be used with spray pumps. This pressure enerated in the conduit J will enter the c inder C and will act on a piston K fitted t erein. The piston is adapted to engage a lever L of the first order fulcrumed on the cylinder or base plate B The other end of this lever is forked-or otherwise shaped to engage a pin or other part c on the lever M fulcrumed on the frame of the machine. The free end of this lever is provided with a projection (1 adapted to enter the helical groove H.

N is a stem slidable through the end of a sleeve 0 screwed into the cylinder C opposite the piston K. The inner end of this stem is adapted to engage theend of the lever L. Its outer end has screwed,thereon a nut (1. Between the end of the sleeve and the head f on the stem is located a coil spring I The sleeve 0 it will be noted may be screwed in or out of the cylinder C. By adjusting the nut a the tension of the spring}? may be adjusted and then by screwing the cylinder N the head f on the stem may be brought into proper engagement with the end of the lever L.

The operation of the device is as follows: Any excess of pressure generated in the conduit forces inward the piston against the tension of the spring P, but of course movement does not take place until the pressure exceeds the resistance of the coil spring, and as already stated the resistance of the latter is adjustable, so that the apparatus may be caused to operate at any desired pressure. I

The movement of the lever L by means of the piston throws up the lever M with its end (1 in engagement with the helical groove H. As the sleeve in which the groove is formed is connected with the movable half of the the groove and allows the parts tr again assume the position shown in Fig. 1 when the driving member is again in clutch with the driven member.

This device. is particularly adapted for power driven spray pumps of all kinds. as Without any attention from the operator the pumping is regulated to at all times maintain a substantial constant pressure wit hout any possibility of excess pressure appearing. The wear and tear on the-pump and othe 1' parts of theapparatus in which the device is used is thus greatly reduced and all danger tofbreak down from excess ressure avoided. I may use this device eit' er with engine driven or" -'.horse power driven pum s.

-I do not desire,

of course, to limit mysef to the precise details of the construction shown, as many va-' riations may be made in the means of operating the levers by excess of pressure and the means for causing the levers to operate the clutch. I v I What I claim as my invention is 1 1. In a device of the class described the combination of a driving member; a driven;

member; a clutch whereby they may be put into or out of gear with one ahother a sleeve rotatable with the driving member connected to the clutch and having a helical grooveformed therein; a lever fulcrumed adjacent to the sleeve and adapted to engage the groove therein; a fluid conduit; and means adapted to be controlled by pressure in the conduit for moving the lever into en agegroove, substantlal y asment with the said described. 7

2. In a device of the class described the combination of a driving member; a driven be put into or out of geanwith one another; a

connected to the clutch and having a helical groove formed therein; a lever fulcrumed ad jacent to the sleeve and adapted to engage the groove therein; a fluid conduit; means adapted to be controlled by pressure in the con ment with the'said groove and an adjustable sgringtensioning device tending to retain t e lever in its normal position; substantially as described.

3. In a device of the class'described the combination of a driving member; a driven member ;.a shifting clutch whereby they may "bepiit'in'toor out of gear with sleeve rotatable with the dr ving memberconnected to the clutch and having a helical one another; a

groove therein; a lever'fulcrumed adjacent to ii -the sleeve and'adapted to engage the roove 7 therein; a fluid conduit; means adapts to be controlled. by. pressure in the conduit for moving thelever into engagement with the saidgroove; an adjustable spring tensioning uit for moving the lever into engage-s I pressure in the conduit above a erases I device tending to retain the lever in its normalpasition and a spring tending to mainconnected to the clutch and having a helical groove formed therein; a lever fulcrumed adjacent to the sleeve and adapted to engage the groove therein; a fluid conduit; a cylinder communicating with the conduit; a PlStOIL therein; a lever of the first order fulcrumed 'ith one endinl contact with the piston and the other in engagement with thejclutch lever; an adjustable spring tensioning device tending to 'maintain'the levers in their normal position; and a spring tending to maintain the clutch in gea substantially as described.

5. In a device of the class described the combination of a dri i'ihg member; a driven member; aclutch whereby they may be put into and out of gear with one another; a slidber, connected to the clutch and having a helical groove formed therein; a shifts-r movably su ported adjacent to the sleeve, and ada te to engage the groove therein;'a fi-uid con uit; and means controlled by' pressure in the conduit for moving the shifter into engagement with the said groove, substantially as described. v j

6. In a device of the class described, the combination of a driving shaft; a driven member on said shaft; a clutch whereby the driving and driven members may be put into and out of gear with one another; a fluid con: duit; means whereby the rotation of said shaft may be utilized to move the'clutch out of gear; and means whereby an increase of predetermined minimum will condition the clutch moving means to operate to throw the clutch out of ear substantially as described.

London, Ont, 22nd June, 1906."

ILLIAM HENRY HEARD. Signed in'the presence of- J. W. SwINNnr'r, R. E. WALKER.

.ing sleeve rotatable with the driving memmember; a shifting clutch wherebythey may 

